This diagram illustrates the wiring for a circuit with gfci receptacles followed by an unprotected light and switch. The light switch is connected directly to the source and the load terminals on the gfci are not used.
This ground fault circuit interrupter wiring diagram of the same device leaves the switch out of the protected circuit. With this arrangement the receptacle is protected but the switch remains outside the circuit. This arrangement can be used to control a light or other device where the extra protection of a gfci is not necessary.
Use this wiring when the source is at the fixture and you want to control the feed to both components with the same switch. Three-wire cable runs from the fan to the switch box and the source neutral is spliced to the white wire and to the fan neutral.
In this diagram, two receptacle outlets are wired in the same box with a separate 120 volt source feeding each. Three-wire cable runs into the box. The black and red wires are hot and each is connected to one of the receptacles. The white, neutral wire is splice to each outlet so they share the return path. This is appropriate for standard duplex receptacles, but should not be used for GFCI receptacles. GFCI’s must have dedicated neutral connections to work properly.